(i) Field of the Invention
The present invention relates to a muscle fatigue level measuring device which estimates the level of fatigue of muscles present in a body part (i.e., muscle fatigue level) based on impedance in the body part.
(ii) Description of the Related Art
Conventional muscle fatigue evaluation devices (muscular fatigue determination devices) place electrodes on a body part so as to measure a change in potential (myoelectric potential) caused by contraction of muscles present in the body part and evaluate (determine) muscle fatigue (muscular fatigue) (for example, refer to Patent Publications 1 and 2).
Patent Publication 1
Japanese Patent Application Laid-Open No. 232/2000
Patent Publication 2
Japanese Patent Application Laid-Open No. 224072/2002
However, the conventional muscle fatigue evaluation devices (muscular fatigue determination devices) have a problem that the electrodes must be placed at the same distance from each other every time the measurement is made because the magnitude of the measured myoelectric potential varies if the distance between the electrodes placed on the body part varies.
Consequently, an object of the present invention is to solve the above problem of the prior art and provide a muscle fatigue level measuring device which estimates a muscle fatigue level without being influenced by a distance between electrodes.